Tsp (1 mM) and retinol (10 mM) were mixed together and
incubated to allow potential binding to occur. A shows the
results of an emission wavelength scan from 380 to 550 nm while holding
the excitation constant at 333 nm. The spectrum was compared with the
same concentration of protein alone and 10 mM all-trans-retinol
alone. The scans show that the mixture of ligand and protein was no
different from the sum of the ligand alone and the protein alone,
suggesting that retinol exhibited no fluorescence enhancement when mixed
with the protein (indicating that Tsp does not bind retinol). B
shows the results of an excitation scan while holding the emission
constant at 479 nm. The results were the same as with the emission scan
and showed no fluorescence enhancement of retinol in the presence of
Tsp, again suggesting that retinol did not bind to Tsp.